Contraception

The Facts

It's important for sexually active people to be aware of the different types of contraception available. Contraception has two primary roles. It prevents unwanted pregnancies as well as the spread of sexually transmitted infections (STIs).

Some people – for instance, those in monogamous (one partner) relationships – might use contraception simply as a means of birth control, while individuals who have more than one sexual partner will also be concerned about getting an STI. Since not all types of contraception prevent STIs, and some forms of birth control are more reliable than others, you need to evaluate which method is best for you and your partner.

Different Types of Contraception

Contraception falls into four main categories, each with its own advantages:

barrier methods

hormonal methods

natural birth control

sterilization

The different types of barrier methods include male condoms, female condoms, diaphragms, and cervical caps. Male condoms are made from latex rubber, vinyl, or natural products, and are unrolled onto an erect penis before having sex. This prevents sperm from reaching the female reproductive tract, and also stops microorganisms from passing from one person to the other (this is true only of latex and vinyl condoms). It goes without saying that if you are allergic to latex, your choice of products is limited.

Female condoms line the vagina and are inserted before intercourse. They are thin, soft pouches made of polyurethane plastic (they can be used by people allergic to latex) with flexible rings at either end. One ring is used to insert the condom, and the other remains outside, covering external genitalia. Female condoms offer greater protection, put control of contraception into women's hands, and avoid the loss of sensation many men feel when wearing male condoms. It takes a bit of practice, however, to learn how to insert the female condom comfortably and correctly. Female condoms are larger than male condoms and are more expensive, costing as much as $3 to $4 each.

Diaphragms and cervical caps do not protect against STIs, including HIV. The diaphragm is a shallow, dome-shaped latex cup, while cervical caps are smaller and thimble-shaped. They fit over the cervix in the vagina, blocking the opening to the uterus. These methods should always be used along with a spermicide (see below). Diaphragms need to be individually fitted, and cervical caps come in four different sizes. In either case, you will need a pelvic exam annually to make sure the fit is still right. Pregnancy, change in weight, and abdominal surgery can all require you to need a different size in diaphragm or cervical cap.

Contraceptive sponges contain spermicide. A sponge is placed at the cervix where the spermicide kills any sperm attempting to enter. The sponge provides 12-hour protection. Some women find it difficult to remove the sponge and some may be allergic to the spermicide. Some women complain of recurrent yeast infections when using the contraceptive sponge. When used in combination with a male condom (it should always be used this way), about 1 in 50 women will become pregnant over the course of one year.

Spermicides are chemicals that inactivate or kill sperm. They're available as creams, gels, aerosols, dissolvable films, and vaginal suppositories or tablets. Some condoms are spermicide-coated for extra protection.

Hormonal methods of contraception rely on the use of progestin, most often in combination with estrogen. These female hormones regulate the reproductive cycle, including menstrual periods and ovulation.

Combined estrogen-progestin* contraceptives are available as oral pills. The packages are designed so that you take your pill once a day, or on a monthly basis for 21 out of 28 days according to directions. After taking the pills for 21 days, you will get your period during the 4th week. After that, a new pack of pills is started to begin a new cycle. There are also some formulations (called "continuous pills") designed to be taken daily for 3 months before missing a week. These give you a period 4 times a year rather than every month. Oral contraceptive pills work by:

suppressing ovulation

thickening the cervical mucus, preventing sperm from getting through

changing the lining of the uterus, making implantation of a fertilized egg less likely

reducing sperm access to the fallopian tubes, where eggs are fertilized

It's important that the pills be taken daily, in the correct order, and on time. The chances of pregnancy increase if one or more pills are missed. In these situations, using additional, back-up contraception such as a barrier method is a good idea.

Combined hormone contraceptives are also available as a patch and as a ring inserted into the vagina. For the patch, one patch is worn on the skin each week for 3 weeks. The fourth week is when you will get your period. Then, the cycle starts again. The vaginal ring is worn inside the vagina for 3 weeks, then removed to allow for a 1-week ring-free interval, during which you will get your period. After this, a new ring is inserted into the vagina.

Progestin-only contraceptives are better suited to some women who shouldn't be taking estrogens, including breast-feeding mothers, women over the age of 35, women who smoke, and women with uncontrolled high blood pressure. If women get migraine headaches (with neurological changes) or have diabetes, sickle cell anemia, or cardiovascular diseases, progestin-only contraceptives are preferred over the combined hormones.

The progestin-only contraceptives work in a similar manner to estrogen-progestin combinations. They can also be taken as daily pills, injections (every 3 months), or as a progestin-releasing intrauterine device (IUD). The intrauterine device (IUD) is a small, T-shaped device that can be fitted into a woman's uterus by her doctor. IUDs release either progestin or copper. Progestin-releasing IUDs work in the same way as other progestin-only contraceptives, and are effective for up to 5 years after which time they must be replaced. These IUDs are the most effective form of reversible contraception and have the added benefit of reduced menstrual flow. The copper-releasing IUD is effective for up to 10 years. Copper affects the lining of the uterus so as to prevent implantation; it also changes the chemistry in the uterus and kills sperm.

Natural birth control methods don't use any spermicides, pills, injections, or other devices. One technique – known as coitus interruptus – requires a man to withdraw his penis completely from the vagina before ejaculation. This is an unreliable method of birth control, since some sperm can be released before ejaculation, and a man must have very good self-control and timing. Approximately 1 out of 5 couples using only this method have an unplanned pregnancy.

Rhythm methods require a woman to abstain from having sex during the most fertile part of the menstrual cycle. A woman can identify when she's ovulating using 1 of 4 techniques: the calendar rhythm, temperature, mucus, and symptothermal methods. The calendar rhythm method is the least accurate of the four. The other methods depend on measurements of body temperature (which slightly falls before and rises after an egg is released) and larger amounts of watery mucus observed before ovulation. Approximately 1 out of 5 women using only the rhythm method of birth control will have an unplanned pregnancy within the first year. Pregnancy risk is further diminished when other monitoring signs are added to the rhythm method.

Sterilization is an option for women and men. For women, this involves tubal ligation, a procedure in which a woman's fallopian tubes are cut and tied, or blocked. This cuts off the sperm's access to the egg, preventing fertilization. For a man, a vasectomy involves cutting the tubes that carry sperm from the testes to the penis. Both methods of sterilization are considered permanent and irreversible, although a very small percentage of men who have had vasectomy reversal may become fertile again.

Side Effects and Complications

There's a 2% to 5% chance that male condoms will tear or slip off, but this is usually associated with inexperience in using them. Handling condoms properly lowers the chances of their tearing or slipping off, and removing a full condom before the penis is soft again helps ensure that sperm won't spill out. On average, approximately 12% of couples using only this method of birth control have an accidental pregnancy.

Women who use diaphragms may be prone to getting bladder infections; this might suggest a poor fit. To lower the chances of infection, urinating before inserting the diaphragm and after intercourse is recommended. Toxic shock syndrome, though very rare, can also occur in diaphragm users. If you experience sudden high fever, diarrhea, vomiting, sore throat, aching joints and muscles, or dizziness, immediately remove the diaphragm and see a doctor.

Women who use spermicides have a higher risk of recurrent urinary tract infections (i.e., 2 or more bladder infections in 6 months). When this happens, switching to a different birth control method can help.

Oral contraceptives are available in many different dosages. Any side effects experienced depend on the individual, and can usually be managed by simply switching to another type of pill. You need to work with your doctor to find the right oral contraceptive for you. In the past, "the pill" has been associated with a higher risk of breast and cervical cancers. Today, however, the dosages of the hormones have been dramatically cut. Talk to your doctor about the risks and benefits of oral contraceptives for you. On the plus side, we do know that oral contraceptives protect women from ovarian and endometrial cancers. Oral contraceptives are considered safe for non-smoking women right up until menopause. Studies suggest that women who smoke should stop using oral contraceptives by age 35 as their risk for heart disease outweighs the benefits of using this method of birth control.

Estrogen in the combination contraceptives can cause side effects such as nausea, headaches, breast tenderness, bloating, and increased blood pressure. There are fewer side effects with progestin-only pills, though progestin can sometimes cause weight gain, acne, and nervousness. Since some medications interfere with the efficiency of oral contraception, women who are taking other medications or who have other medical conditions should consult their doctors.

The reliability of contraception varies greatly among methods. Approximate percentages of women who get pregnant during the first year of using a particular form of contraception alone are as follows (where a range of percentages exist, the lower number refers to "perfect" use of the method and the higher number refers to "real world" scenarios):

male condoms: 3% to 12%

female condoms: 5% to 21%

male condom plus contraceptive sponge: 2%

diaphragm with spermicide: 6% to 18%

cervical caps with spermicide: 11.5% to 18%

oral estrogen-progestin pills: 0.3% to 3%

oral progestin-only pills: 0.5% to 3%

estrogen-progestin patch: 0.3% to 3%

estrogen-progestin ring: 0.3% to 3%

injectable progestin: 0.3%

progestin implants: less than 0.1%

intrauterine devices: 0.6% to 2%

rhythm method (natural contraception): 20%

tubal ligation: 2% (in a 10-year period)

withdrawal: 20%

vasectomy: less than 1%

Emergency contraception – sometimes called the "morning-after pill" – is used in some cases to prevent pregnancy after unprotected sex. These are available from your doctor or from women's health clinics or, in many provinces, from pharmacies. They should be taken within 72 hours of unprotected intercourse. Approximately 99% of unplanned pregnancies can be avoided using this method. Inserting an IUD is sometimes used as an alternative form of emergency contraception, especially if more than 72 hours has elapsed since unprotected sex.

*All medications have both common (generic) and brand names. The brand name is what a specific manufacturer calls the product (e.g., Tylenol®). The common name is the medical name for the medication (e.g., acetaminophen). A medication may have many brand names, but only one common name. This article lists medications by their common names. For information on a given medication, check our Drug Information database. For more information on brand names, speak with your doctor or pharmacist.